As well as being an accomplished jazz pianist, he was most famous for being the conductor of many Irish entries to the Eurovision Song Contest, beginning in 1966 and ending in 1998. He conducted five winning Irish entries, in 1980, 1987, 1992, 1993, and 1996. In 1994, the winning song was performed without orchestral accompaniment. However, an entry rated second that year, "To nie ja!" performed by Edyta Górniak from Poland, was also conducted by Kelehan. He also conducted entry from Bosnia and Herzegovina in 1993. In total, Kelehan conducted 29 Eurovision entries, 24 of them Irish. In 1999, after Kelehan retired, the use of an orchestra was discontinued at the Contest.

He died at the age of 76, in Dublin on 6 February 2012, after a long illness.[1] His funeral took place in Dublin on 9 February 2012.[2]

Kelehan had several records to his credit; most notably, with the Noel Kelehan Quintet he recorded the album "Ozone" in 1979. In 1984 he wrote the string arrangements for U2's album The Unforgettable Fire.[3][4]